Having trouble picking a name for a younger brother to Ruby

Hi all,

My wife and I are struggling with picking a name for our son, who is due at the end of July. Our almost two-year-old daughter is named Ruby, and we feel that it fits her perfectly!

We have come up with a handful of "maybe" names, but nothing has stuck so far – Elijah, Milo, Calvin, Matthew are all names which we've played with so far but are not 100% sold on.

Style wise, we're aiming for something quite timeless and would be suitable for any age, much like Ruby is, while trying to avoid the standards like Michael, William, Steven, or Brian, or going too fancy and modern and ending in Tragedeigh.

(I know Matthew is more or less a commonplace name, but I've been considering it as a way to honour my cousin who passed away last summer as we were quite close. I would be okay with using it as a middle name if it made sense.)

At this point it feels like the two of us have exhausted every baby name list on the internet, so I'm hoping maybe someone has a hidden gem in their back pocket.

I'll do my best to answer questions if anyone needs more information. Thank you for your help!